1 /* Copyright (c) 2013 Coraid, Inc. See COPYING for GPL terms. */ 2 /* 3 * aoecmd.c 4 * Filesystem request handling methods 5 */ 6 7 #include <linux/ata.h> 8 #include <linux/slab.h> 9 #include <linux/hdreg.h> 10 #include <linux/blkdev.h> 11 #include <linux/skbuff.h> 12 #include <linux/netdevice.h> 13 #include <linux/genhd.h> 14 #include <linux/moduleparam.h> 15 #include <linux/workqueue.h> 16 #include <linux/kthread.h> 17 #include <net/net_namespace.h> 18 #include <asm/unaligned.h> 19 #include <linux/uio.h> 20 #include "aoe.h" 21 22 #define MAXIOC (8192) /* default meant to avoid most soft lockups */ 23 24 static void ktcomplete(struct frame *, struct sk_buff *); 25 static int count_targets(struct aoedev *d, int *untainted); 26 27 static struct buf *nextbuf(struct aoedev *); 28 29 static int aoe_deadsecs = 60 * 3; 30 module_param(aoe_deadsecs, int, 0644); 31 MODULE_PARM_DESC(aoe_deadsecs, "After aoe_deadsecs seconds, give up and fail dev."); 32 33 static int aoe_maxout = 64; 34 module_param(aoe_maxout, int, 0644); 35 MODULE_PARM_DESC(aoe_maxout, 36 "Only aoe_maxout outstanding packets for every MAC on eX.Y."); 37 38 /* The number of online cpus during module initialization gives us a 39 * convenient heuristic cap on the parallelism used for ktio threads 40 * doing I/O completion. It is not important that the cap equal the 41 * actual number of running CPUs at any given time, but because of CPU 42 * hotplug, we take care to use ncpus instead of using 43 * num_online_cpus() after module initialization. 44 */ 45 static int ncpus; 46 47 /* mutex lock used for synchronization while thread spawning */ 48 static DEFINE_MUTEX(ktio_spawn_lock); 49 50 static wait_queue_head_t *ktiowq; 51 static struct ktstate *kts; 52 53 /* io completion queue */ 54 struct iocq_ktio { 55 struct list_head head; 56 spinlock_t lock; 57 }; 58 static struct iocq_ktio *iocq; 59 60 static struct page *empty_page; 61 62 static struct sk_buff * 63 new_skb(ulong len) 64 { 65 struct sk_buff *skb; 66 67 skb = alloc_skb(len + MAX_HEADER, GFP_ATOMIC); 68 if (skb) { 69 skb_reserve(skb, MAX_HEADER); 70 skb_reset_mac_header(skb); 71 skb_reset_network_header(skb); 72 skb->protocol = __constant_htons(ETH_P_AOE); 73 skb_checksum_none_assert(skb); 74 } 75 return skb; 76 } 77 78 static struct frame * 79 getframe_deferred(struct aoedev *d, u32 tag) 80 { 81 struct list_head *head, *pos, *nx; 82 struct frame *f; 83 84 head = &d->rexmitq; 85 list_for_each_safe(pos, nx, head) { 86 f = list_entry(pos, struct frame, head); 87 if (f->tag == tag) { 88 list_del(pos); 89 return f; 90 } 91 } 92 return NULL; 93 } 94 95 static struct frame * 96 getframe(struct aoedev *d, u32 tag) 97 { 98 struct frame *f; 99 struct list_head *head, *pos, *nx; 100 u32 n; 101 102 n = tag % NFACTIVE; 103 head = &d->factive[n]; 104 list_for_each_safe(pos, nx, head) { 105 f = list_entry(pos, struct frame, head); 106 if (f->tag == tag) { 107 list_del(pos); 108 return f; 109 } 110 } 111 return NULL; 112 } 113 114 /* 115 * Leave the top bit clear so we have tagspace for userland. 116 * The bottom 16 bits are the xmit tick for rexmit/rttavg processing. 117 * This driver reserves tag -1 to mean "unused frame." 118 */ 119 static int 120 newtag(struct aoedev *d) 121 { 122 register ulong n; 123 124 n = jiffies & 0xffff; 125 return n |= (++d->lasttag & 0x7fff) << 16; 126 } 127 128 static u32 129 aoehdr_atainit(struct aoedev *d, struct aoetgt *t, struct aoe_hdr *h) 130 { 131 u32 host_tag = newtag(d); 132 133 memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src); 134 memcpy(h->dst, t->addr, sizeof h->dst); 135 h->type = __constant_cpu_to_be16(ETH_P_AOE); 136 h->verfl = AOE_HVER; 137 h->major = cpu_to_be16(d->aoemajor); 138 h->minor = d->aoeminor; 139 h->cmd = AOECMD_ATA; 140 h->tag = cpu_to_be32(host_tag); 141 142 return host_tag; 143 } 144 145 static inline void 146 put_lba(struct aoe_atahdr *ah, sector_t lba) 147 { 148 ah->lba0 = lba; 149 ah->lba1 = lba >>= 8; 150 ah->lba2 = lba >>= 8; 151 ah->lba3 = lba >>= 8; 152 ah->lba4 = lba >>= 8; 153 ah->lba5 = lba >>= 8; 154 } 155 156 static struct aoeif * 157 ifrotate(struct aoetgt *t) 158 { 159 struct aoeif *ifp; 160 161 ifp = t->ifp; 162 ifp++; 163 if (ifp >= &t->ifs[NAOEIFS] || ifp->nd == NULL) 164 ifp = t->ifs; 165 if (ifp->nd == NULL) 166 return NULL; 167 return t->ifp = ifp; 168 } 169 170 static void 171 skb_pool_put(struct aoedev *d, struct sk_buff *skb) 172 { 173 __skb_queue_tail(&d->skbpool, skb); 174 } 175 176 static struct sk_buff * 177 skb_pool_get(struct aoedev *d) 178 { 179 struct sk_buff *skb = skb_peek(&d->skbpool); 180 181 if (skb && atomic_read(&skb_shinfo(skb)->dataref) == 1) { 182 __skb_unlink(skb, &d->skbpool); 183 return skb; 184 } 185 if (skb_queue_len(&d->skbpool) < NSKBPOOLMAX && 186 (skb = new_skb(ETH_ZLEN))) 187 return skb; 188 189 return NULL; 190 } 191 192 void 193 aoe_freetframe(struct frame *f) 194 { 195 struct aoetgt *t; 196 197 t = f->t; 198 f->buf = NULL; 199 memset(&f->iter, 0, sizeof(f->iter)); 200 f->r_skb = NULL; 201 f->flags = 0; 202 list_add(&f->head, &t->ffree); 203 } 204 205 static struct frame * 206 newtframe(struct aoedev *d, struct aoetgt *t) 207 { 208 struct frame *f; 209 struct sk_buff *skb; 210 struct list_head *pos; 211 212 if (list_empty(&t->ffree)) { 213 if (t->falloc >= NSKBPOOLMAX*2) 214 return NULL; 215 f = kcalloc(1, sizeof(*f), GFP_ATOMIC); 216 if (f == NULL) 217 return NULL; 218 t->falloc++; 219 f->t = t; 220 } else { 221 pos = t->ffree.next; 222 list_del(pos); 223 f = list_entry(pos, struct frame, head); 224 } 225 226 skb = f->skb; 227 if (skb == NULL) { 228 f->skb = skb = new_skb(ETH_ZLEN); 229 if (!skb) { 230 bail: aoe_freetframe(f); 231 return NULL; 232 } 233 } 234 235 if (atomic_read(&skb_shinfo(skb)->dataref) != 1) { 236 skb = skb_pool_get(d); 237 if (skb == NULL) 238 goto bail; 239 skb_pool_put(d, f->skb); 240 f->skb = skb; 241 } 242 243 skb->truesize -= skb->data_len; 244 skb_shinfo(skb)->nr_frags = skb->data_len = 0; 245 skb_trim(skb, 0); 246 return f; 247 } 248 249 static struct frame * 250 newframe(struct aoedev *d) 251 { 252 struct frame *f; 253 struct aoetgt *t, **tt; 254 int totout = 0; 255 int use_tainted; 256 int has_untainted; 257 258 if (!d->targets || !d->targets[0]) { 259 printk(KERN_ERR "aoe: NULL TARGETS!\n"); 260 return NULL; 261 } 262 tt = d->tgt; /* last used target */ 263 for (use_tainted = 0, has_untainted = 0;;) { 264 tt++; 265 if (tt >= &d->targets[d->ntargets] || !*tt) 266 tt = d->targets; 267 t = *tt; 268 if (!t->taint) { 269 has_untainted = 1; 270 totout += t->nout; 271 } 272 if (t->nout < t->maxout 273 && (use_tainted || !t->taint) 274 && t->ifp->nd) { 275 f = newtframe(d, t); 276 if (f) { 277 ifrotate(t); 278 d->tgt = tt; 279 return f; 280 } 281 } 282 if (tt == d->tgt) { /* we've looped and found nada */ 283 if (!use_tainted && !has_untainted) 284 use_tainted = 1; 285 else 286 break; 287 } 288 } 289 if (totout == 0) { 290 d->kicked++; 291 d->flags |= DEVFL_KICKME; 292 } 293 return NULL; 294 } 295 296 static void 297 skb_fillup(struct sk_buff *skb, struct bio *bio, struct bvec_iter iter) 298 { 299 int frag = 0; 300 struct bio_vec bv; 301 302 __bio_for_each_segment(bv, bio, iter, iter) 303 skb_fill_page_desc(skb, frag++, bv.bv_page, 304 bv.bv_offset, bv.bv_len); 305 } 306 307 static void 308 fhash(struct frame *f) 309 { 310 struct aoedev *d = f->t->d; 311 u32 n; 312 313 n = f->tag % NFACTIVE; 314 list_add_tail(&f->head, &d->factive[n]); 315 } 316 317 static void 318 ata_rw_frameinit(struct frame *f) 319 { 320 struct aoetgt *t; 321 struct aoe_hdr *h; 322 struct aoe_atahdr *ah; 323 struct sk_buff *skb; 324 char writebit, extbit; 325 326 skb = f->skb; 327 h = (struct aoe_hdr *) skb_mac_header(skb); 328 ah = (struct aoe_atahdr *) (h + 1); 329 skb_put(skb, sizeof(*h) + sizeof(*ah)); 330 memset(h, 0, skb->len); 331 332 writebit = 0x10; 333 extbit = 0x4; 334 335 t = f->t; 336 f->tag = aoehdr_atainit(t->d, t, h); 337 fhash(f); 338 t->nout++; 339 f->waited = 0; 340 f->waited_total = 0; 341 342 /* set up ata header */ 343 ah->scnt = f->iter.bi_size >> 9; 344 put_lba(ah, f->iter.bi_sector); 345 if (t->d->flags & DEVFL_EXT) { 346 ah->aflags |= AOEAFL_EXT; 347 } else { 348 extbit = 0; 349 ah->lba3 &= 0x0f; 350 ah->lba3 |= 0xe0; /* LBA bit + obsolete 0xa0 */ 351 } 352 if (f->buf && bio_data_dir(f->buf->bio) == WRITE) { 353 skb_fillup(skb, f->buf->bio, f->iter); 354 ah->aflags |= AOEAFL_WRITE; 355 skb->len += f->iter.bi_size; 356 skb->data_len = f->iter.bi_size; 357 skb->truesize += f->iter.bi_size; 358 t->wpkts++; 359 } else { 360 t->rpkts++; 361 writebit = 0; 362 } 363 364 ah->cmdstat = ATA_CMD_PIO_READ | writebit | extbit; 365 skb->dev = t->ifp->nd; 366 } 367 368 static int 369 aoecmd_ata_rw(struct aoedev *d) 370 { 371 struct frame *f; 372 struct buf *buf; 373 struct sk_buff *skb; 374 struct sk_buff_head queue; 375 376 buf = nextbuf(d); 377 if (buf == NULL) 378 return 0; 379 f = newframe(d); 380 if (f == NULL) 381 return 0; 382 383 /* initialize the headers & frame */ 384 f->buf = buf; 385 f->iter = buf->iter; 386 f->iter.bi_size = min_t(unsigned long, 387 d->maxbcnt ?: DEFAULTBCNT, 388 f->iter.bi_size); 389 bio_advance_iter(buf->bio, &buf->iter, f->iter.bi_size); 390 391 if (!buf->iter.bi_size) 392 d->ip.buf = NULL; 393 394 /* mark all tracking fields and load out */ 395 buf->nframesout += 1; 396 397 ata_rw_frameinit(f); 398 399 skb = skb_clone(f->skb, GFP_ATOMIC); 400 if (skb) { 401 do_gettimeofday(&f->sent); 402 f->sent_jiffs = (u32) jiffies; 403 __skb_queue_head_init(&queue); 404 __skb_queue_tail(&queue, skb); 405 aoenet_xmit(&queue); 406 } 407 return 1; 408 } 409 410 /* some callers cannot sleep, and they can call this function, 411 * transmitting the packets later, when interrupts are on 412 */ 413 static void 414 aoecmd_cfg_pkts(ushort aoemajor, unsigned char aoeminor, struct sk_buff_head *queue) 415 { 416 struct aoe_hdr *h; 417 struct aoe_cfghdr *ch; 418 struct sk_buff *skb; 419 struct net_device *ifp; 420 421 rcu_read_lock(); 422 for_each_netdev_rcu(&init_net, ifp) { 423 dev_hold(ifp); 424 if (!is_aoe_netif(ifp)) 425 goto cont; 426 427 skb = new_skb(sizeof *h + sizeof *ch); 428 if (skb == NULL) { 429 printk(KERN_INFO "aoe: skb alloc failure\n"); 430 goto cont; 431 } 432 skb_put(skb, sizeof *h + sizeof *ch); 433 skb->dev = ifp; 434 __skb_queue_tail(queue, skb); 435 h = (struct aoe_hdr *) skb_mac_header(skb); 436 memset(h, 0, sizeof *h + sizeof *ch); 437 438 memset(h->dst, 0xff, sizeof h->dst); 439 memcpy(h->src, ifp->dev_addr, sizeof h->src); 440 h->type = __constant_cpu_to_be16(ETH_P_AOE); 441 h->verfl = AOE_HVER; 442 h->major = cpu_to_be16(aoemajor); 443 h->minor = aoeminor; 444 h->cmd = AOECMD_CFG; 445 446 cont: 447 dev_put(ifp); 448 } 449 rcu_read_unlock(); 450 } 451 452 static void 453 resend(struct aoedev *d, struct frame *f) 454 { 455 struct sk_buff *skb; 456 struct sk_buff_head queue; 457 struct aoe_hdr *h; 458 struct aoetgt *t; 459 char buf[128]; 460 u32 n; 461 462 t = f->t; 463 n = newtag(d); 464 skb = f->skb; 465 if (ifrotate(t) == NULL) { 466 /* probably can't happen, but set it up to fail anyway */ 467 pr_info("aoe: resend: no interfaces to rotate to.\n"); 468 ktcomplete(f, NULL); 469 return; 470 } 471 h = (struct aoe_hdr *) skb_mac_header(skb); 472 473 if (!(f->flags & FFL_PROBE)) { 474 snprintf(buf, sizeof(buf), 475 "%15s e%ld.%d oldtag=%08x@%08lx newtag=%08x s=%pm d=%pm nout=%d\n", 476 "retransmit", d->aoemajor, d->aoeminor, 477 f->tag, jiffies, n, 478 h->src, h->dst, t->nout); 479 aoechr_error(buf); 480 } 481 482 f->tag = n; 483 fhash(f); 484 h->tag = cpu_to_be32(n); 485 memcpy(h->dst, t->addr, sizeof h->dst); 486 memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src); 487 488 skb->dev = t->ifp->nd; 489 skb = skb_clone(skb, GFP_ATOMIC); 490 if (skb == NULL) 491 return; 492 do_gettimeofday(&f->sent); 493 f->sent_jiffs = (u32) jiffies; 494 __skb_queue_head_init(&queue); 495 __skb_queue_tail(&queue, skb); 496 aoenet_xmit(&queue); 497 } 498 499 static int 500 tsince_hr(struct frame *f) 501 { 502 struct timeval now; 503 int n; 504 505 do_gettimeofday(&now); 506 n = now.tv_usec - f->sent.tv_usec; 507 n += (now.tv_sec - f->sent.tv_sec) * USEC_PER_SEC; 508 509 if (n < 0) 510 n = -n; 511 512 /* For relatively long periods, use jiffies to avoid 513 * discrepancies caused by updates to the system time. 514 * 515 * On system with HZ of 1000, 32-bits is over 49 days 516 * worth of jiffies, or over 71 minutes worth of usecs. 517 * 518 * Jiffies overflow is handled by subtraction of unsigned ints: 519 * (gdb) print (unsigned) 2 - (unsigned) 0xfffffffe 520 * $3 = 4 521 * (gdb) 522 */ 523 if (n > USEC_PER_SEC / 4) { 524 n = ((u32) jiffies) - f->sent_jiffs; 525 n *= USEC_PER_SEC / HZ; 526 } 527 528 return n; 529 } 530 531 static int 532 tsince(u32 tag) 533 { 534 int n; 535 536 n = jiffies & 0xffff; 537 n -= tag & 0xffff; 538 if (n < 0) 539 n += 1<<16; 540 return jiffies_to_usecs(n + 1); 541 } 542 543 static struct aoeif * 544 getif(struct aoetgt *t, struct net_device *nd) 545 { 546 struct aoeif *p, *e; 547 548 p = t->ifs; 549 e = p + NAOEIFS; 550 for (; p < e; p++) 551 if (p->nd == nd) 552 return p; 553 return NULL; 554 } 555 556 static void 557 ejectif(struct aoetgt *t, struct aoeif *ifp) 558 { 559 struct aoeif *e; 560 struct net_device *nd; 561 ulong n; 562 563 nd = ifp->nd; 564 e = t->ifs + NAOEIFS - 1; 565 n = (e - ifp) * sizeof *ifp; 566 memmove(ifp, ifp+1, n); 567 e->nd = NULL; 568 dev_put(nd); 569 } 570 571 static struct frame * 572 reassign_frame(struct frame *f) 573 { 574 struct frame *nf; 575 struct sk_buff *skb; 576 577 nf = newframe(f->t->d); 578 if (!nf) 579 return NULL; 580 if (nf->t == f->t) { 581 aoe_freetframe(nf); 582 return NULL; 583 } 584 585 skb = nf->skb; 586 nf->skb = f->skb; 587 nf->buf = f->buf; 588 nf->iter = f->iter; 589 nf->waited = 0; 590 nf->waited_total = f->waited_total; 591 nf->sent = f->sent; 592 nf->sent_jiffs = f->sent_jiffs; 593 f->skb = skb; 594 595 return nf; 596 } 597 598 static void 599 probe(struct aoetgt *t) 600 { 601 struct aoedev *d; 602 struct frame *f; 603 struct sk_buff *skb; 604 struct sk_buff_head queue; 605 size_t n, m; 606 int frag; 607 608 d = t->d; 609 f = newtframe(d, t); 610 if (!f) { 611 pr_err("%s %pm for e%ld.%d: %s\n", 612 "aoe: cannot probe remote address", 613 t->addr, 614 (long) d->aoemajor, d->aoeminor, 615 "no frame available"); 616 return; 617 } 618 f->flags |= FFL_PROBE; 619 ifrotate(t); 620 f->iter.bi_size = t->d->maxbcnt ? t->d->maxbcnt : DEFAULTBCNT; 621 ata_rw_frameinit(f); 622 skb = f->skb; 623 for (frag = 0, n = f->iter.bi_size; n > 0; ++frag, n -= m) { 624 if (n < PAGE_SIZE) 625 m = n; 626 else 627 m = PAGE_SIZE; 628 skb_fill_page_desc(skb, frag, empty_page, 0, m); 629 } 630 skb->len += f->iter.bi_size; 631 skb->data_len = f->iter.bi_size; 632 skb->truesize += f->iter.bi_size; 633 634 skb = skb_clone(f->skb, GFP_ATOMIC); 635 if (skb) { 636 do_gettimeofday(&f->sent); 637 f->sent_jiffs = (u32) jiffies; 638 __skb_queue_head_init(&queue); 639 __skb_queue_tail(&queue, skb); 640 aoenet_xmit(&queue); 641 } 642 } 643 644 static long 645 rto(struct aoedev *d) 646 { 647 long t; 648 649 t = 2 * d->rttavg >> RTTSCALE; 650 t += 8 * d->rttdev >> RTTDSCALE; 651 if (t == 0) 652 t = 1; 653 654 return t; 655 } 656 657 static void 658 rexmit_deferred(struct aoedev *d) 659 { 660 struct aoetgt *t; 661 struct frame *f; 662 struct frame *nf; 663 struct list_head *pos, *nx, *head; 664 int since; 665 int untainted; 666 667 count_targets(d, &untainted); 668 669 head = &d->rexmitq; 670 list_for_each_safe(pos, nx, head) { 671 f = list_entry(pos, struct frame, head); 672 t = f->t; 673 if (t->taint) { 674 if (!(f->flags & FFL_PROBE)) { 675 nf = reassign_frame(f); 676 if (nf) { 677 if (t->nout_probes == 0 678 && untainted > 0) { 679 probe(t); 680 t->nout_probes++; 681 } 682 list_replace(&f->head, &nf->head); 683 pos = &nf->head; 684 aoe_freetframe(f); 685 f = nf; 686 t = f->t; 687 } 688 } else if (untainted < 1) { 689 /* don't probe w/o other untainted aoetgts */ 690 goto stop_probe; 691 } else if (tsince_hr(f) < t->taint * rto(d)) { 692 /* reprobe slowly when taint is high */ 693 continue; 694 } 695 } else if (f->flags & FFL_PROBE) { 696 stop_probe: /* don't probe untainted aoetgts */ 697 list_del(pos); 698 aoe_freetframe(f); 699 /* leaving d->kicked, because this is routine */ 700 f->t->d->flags |= DEVFL_KICKME; 701 continue; 702 } 703 if (t->nout >= t->maxout) 704 continue; 705 list_del(pos); 706 t->nout++; 707 if (f->flags & FFL_PROBE) 708 t->nout_probes++; 709 since = tsince_hr(f); 710 f->waited += since; 711 f->waited_total += since; 712 resend(d, f); 713 } 714 } 715 716 /* An aoetgt accumulates demerits quickly, and successful 717 * probing redeems the aoetgt slowly. 718 */ 719 static void 720 scorn(struct aoetgt *t) 721 { 722 int n; 723 724 n = t->taint++; 725 t->taint += t->taint * 2; 726 if (n > t->taint) 727 t->taint = n; 728 if (t->taint > MAX_TAINT) 729 t->taint = MAX_TAINT; 730 } 731 732 static int 733 count_targets(struct aoedev *d, int *untainted) 734 { 735 int i, good; 736 737 for (i = good = 0; i < d->ntargets && d->targets[i]; ++i) 738 if (d->targets[i]->taint == 0) 739 good++; 740 741 if (untainted) 742 *untainted = good; 743 return i; 744 } 745 746 static void 747 rexmit_timer(ulong vp) 748 { 749 struct aoedev *d; 750 struct aoetgt *t; 751 struct aoeif *ifp; 752 struct frame *f; 753 struct list_head *head, *pos, *nx; 754 LIST_HEAD(flist); 755 register long timeout; 756 ulong flags, n; 757 int i; 758 int utgts; /* number of aoetgt descriptors (not slots) */ 759 int since; 760 761 d = (struct aoedev *) vp; 762 763 spin_lock_irqsave(&d->lock, flags); 764 765 /* timeout based on observed timings and variations */ 766 timeout = rto(d); 767 768 utgts = count_targets(d, NULL); 769 770 if (d->flags & DEVFL_TKILL) { 771 spin_unlock_irqrestore(&d->lock, flags); 772 return; 773 } 774 775 /* collect all frames to rexmit into flist */ 776 for (i = 0; i < NFACTIVE; i++) { 777 head = &d->factive[i]; 778 list_for_each_safe(pos, nx, head) { 779 f = list_entry(pos, struct frame, head); 780 if (tsince_hr(f) < timeout) 781 break; /* end of expired frames */ 782 /* move to flist for later processing */ 783 list_move_tail(pos, &flist); 784 } 785 } 786 787 /* process expired frames */ 788 while (!list_empty(&flist)) { 789 pos = flist.next; 790 f = list_entry(pos, struct frame, head); 791 since = tsince_hr(f); 792 n = f->waited_total + since; 793 n /= USEC_PER_SEC; 794 if (aoe_deadsecs 795 && n > aoe_deadsecs 796 && !(f->flags & FFL_PROBE)) { 797 /* Waited too long. Device failure. 798 * Hang all frames on first hash bucket for downdev 799 * to clean up. 800 */ 801 list_splice(&flist, &d->factive[0]); 802 aoedev_downdev(d); 803 goto out; 804 } 805 806 t = f->t; 807 n = f->waited + since; 808 n /= USEC_PER_SEC; 809 if (aoe_deadsecs && utgts > 0 810 && (n > aoe_deadsecs / utgts || n > HARD_SCORN_SECS)) 811 scorn(t); /* avoid this target */ 812 813 if (t->maxout != 1) { 814 t->ssthresh = t->maxout / 2; 815 t->maxout = 1; 816 } 817 818 if (f->flags & FFL_PROBE) { 819 t->nout_probes--; 820 } else { 821 ifp = getif(t, f->skb->dev); 822 if (ifp && ++ifp->lost > (t->nframes << 1) 823 && (ifp != t->ifs || t->ifs[1].nd)) { 824 ejectif(t, ifp); 825 ifp = NULL; 826 } 827 } 828 list_move_tail(pos, &d->rexmitq); 829 t->nout--; 830 } 831 rexmit_deferred(d); 832 833 out: 834 if ((d->flags & DEVFL_KICKME) && d->blkq) { 835 d->flags &= ~DEVFL_KICKME; 836 d->blkq->request_fn(d->blkq); 837 } 838 839 d->timer.expires = jiffies + TIMERTICK; 840 add_timer(&d->timer); 841 842 spin_unlock_irqrestore(&d->lock, flags); 843 } 844 845 static unsigned long 846 rqbiocnt(struct request *r) 847 { 848 struct bio *bio; 849 unsigned long n = 0; 850 851 __rq_for_each_bio(bio, r) 852 n++; 853 return n; 854 } 855 856 /* This can be removed if we are certain that no users of the block 857 * layer will ever use zero-count pages in bios. Otherwise we have to 858 * protect against the put_page sometimes done by the network layer. 859 * 860 * See http://oss.sgi.com/archives/xfs/2007-01/msg00594.html for 861 * discussion. 862 * 863 * We cannot use get_page in the workaround, because it insists on a 864 * positive page count as a precondition. So we use _count directly. 865 */ 866 static void 867 bio_pageinc(struct bio *bio) 868 { 869 struct bio_vec bv; 870 struct page *page; 871 struct bvec_iter iter; 872 873 bio_for_each_segment(bv, bio, iter) { 874 /* Non-zero page count for non-head members of 875 * compound pages is no longer allowed by the kernel. 876 */ 877 page = compound_head(bv.bv_page); 878 atomic_inc(&page->_count); 879 } 880 } 881 882 static void 883 bio_pagedec(struct bio *bio) 884 { 885 struct page *page; 886 struct bio_vec bv; 887 struct bvec_iter iter; 888 889 bio_for_each_segment(bv, bio, iter) { 890 page = compound_head(bv.bv_page); 891 atomic_dec(&page->_count); 892 } 893 } 894 895 static void 896 bufinit(struct buf *buf, struct request *rq, struct bio *bio) 897 { 898 memset(buf, 0, sizeof(*buf)); 899 buf->rq = rq; 900 buf->bio = bio; 901 buf->iter = bio->bi_iter; 902 bio_pageinc(bio); 903 } 904 905 static struct buf * 906 nextbuf(struct aoedev *d) 907 { 908 struct request *rq; 909 struct request_queue *q; 910 struct buf *buf; 911 struct bio *bio; 912 913 q = d->blkq; 914 if (q == NULL) 915 return NULL; /* initializing */ 916 if (d->ip.buf) 917 return d->ip.buf; 918 rq = d->ip.rq; 919 if (rq == NULL) { 920 rq = blk_peek_request(q); 921 if (rq == NULL) 922 return NULL; 923 blk_start_request(rq); 924 d->ip.rq = rq; 925 d->ip.nxbio = rq->bio; 926 rq->special = (void *) rqbiocnt(rq); 927 } 928 buf = mempool_alloc(d->bufpool, GFP_ATOMIC); 929 if (buf == NULL) { 930 pr_err("aoe: nextbuf: unable to mempool_alloc!\n"); 931 return NULL; 932 } 933 bio = d->ip.nxbio; 934 bufinit(buf, rq, bio); 935 bio = bio->bi_next; 936 d->ip.nxbio = bio; 937 if (bio == NULL) 938 d->ip.rq = NULL; 939 return d->ip.buf = buf; 940 } 941 942 /* enters with d->lock held */ 943 void 944 aoecmd_work(struct aoedev *d) 945 { 946 rexmit_deferred(d); 947 while (aoecmd_ata_rw(d)) 948 ; 949 } 950 951 /* this function performs work that has been deferred until sleeping is OK 952 */ 953 void 954 aoecmd_sleepwork(struct work_struct *work) 955 { 956 struct aoedev *d = container_of(work, struct aoedev, work); 957 struct block_device *bd; 958 u64 ssize; 959 960 if (d->flags & DEVFL_GDALLOC) 961 aoeblk_gdalloc(d); 962 963 if (d->flags & DEVFL_NEWSIZE) { 964 ssize = get_capacity(d->gd); 965 bd = bdget_disk(d->gd, 0); 966 if (bd) { 967 inode_lock(bd->bd_inode); 968 i_size_write(bd->bd_inode, (loff_t)ssize<<9); 969 inode_unlock(bd->bd_inode); 970 bdput(bd); 971 } 972 spin_lock_irq(&d->lock); 973 d->flags |= DEVFL_UP; 974 d->flags &= ~DEVFL_NEWSIZE; 975 spin_unlock_irq(&d->lock); 976 } 977 } 978 979 static void 980 ata_ident_fixstring(u16 *id, int ns) 981 { 982 u16 s; 983 984 while (ns-- > 0) { 985 s = *id; 986 *id++ = s >> 8 | s << 8; 987 } 988 } 989 990 static void 991 ataid_complete(struct aoedev *d, struct aoetgt *t, unsigned char *id) 992 { 993 u64 ssize; 994 u16 n; 995 996 /* word 83: command set supported */ 997 n = get_unaligned_le16(&id[83 << 1]); 998 999 /* word 86: command set/feature enabled */ 1000 n |= get_unaligned_le16(&id[86 << 1]); 1001 1002 if (n & (1<<10)) { /* bit 10: LBA 48 */ 1003 d->flags |= DEVFL_EXT; 1004 1005 /* word 100: number lba48 sectors */ 1006 ssize = get_unaligned_le64(&id[100 << 1]); 1007 1008 /* set as in ide-disk.c:init_idedisk_capacity */ 1009 d->geo.cylinders = ssize; 1010 d->geo.cylinders /= (255 * 63); 1011 d->geo.heads = 255; 1012 d->geo.sectors = 63; 1013 } else { 1014 d->flags &= ~DEVFL_EXT; 1015 1016 /* number lba28 sectors */ 1017 ssize = get_unaligned_le32(&id[60 << 1]); 1018 1019 /* NOTE: obsolete in ATA 6 */ 1020 d->geo.cylinders = get_unaligned_le16(&id[54 << 1]); 1021 d->geo.heads = get_unaligned_le16(&id[55 << 1]); 1022 d->geo.sectors = get_unaligned_le16(&id[56 << 1]); 1023 } 1024 1025 ata_ident_fixstring((u16 *) &id[10<<1], 10); /* serial */ 1026 ata_ident_fixstring((u16 *) &id[23<<1], 4); /* firmware */ 1027 ata_ident_fixstring((u16 *) &id[27<<1], 20); /* model */ 1028 memcpy(d->ident, id, sizeof(d->ident)); 1029 1030 if (d->ssize != ssize) 1031 printk(KERN_INFO 1032 "aoe: %pm e%ld.%d v%04x has %llu sectors\n", 1033 t->addr, 1034 d->aoemajor, d->aoeminor, 1035 d->fw_ver, (long long)ssize); 1036 d->ssize = ssize; 1037 d->geo.start = 0; 1038 if (d->flags & (DEVFL_GDALLOC|DEVFL_NEWSIZE)) 1039 return; 1040 if (d->gd != NULL) { 1041 set_capacity(d->gd, ssize); 1042 d->flags |= DEVFL_NEWSIZE; 1043 } else 1044 d->flags |= DEVFL_GDALLOC; 1045 schedule_work(&d->work); 1046 } 1047 1048 static void 1049 calc_rttavg(struct aoedev *d, struct aoetgt *t, int rtt) 1050 { 1051 register long n; 1052 1053 n = rtt; 1054 1055 /* cf. Congestion Avoidance and Control, Jacobson & Karels, 1988 */ 1056 n -= d->rttavg >> RTTSCALE; 1057 d->rttavg += n; 1058 if (n < 0) 1059 n = -n; 1060 n -= d->rttdev >> RTTDSCALE; 1061 d->rttdev += n; 1062 1063 if (!t || t->maxout >= t->nframes) 1064 return; 1065 if (t->maxout < t->ssthresh) 1066 t->maxout += 1; 1067 else if (t->nout == t->maxout && t->next_cwnd-- == 0) { 1068 t->maxout += 1; 1069 t->next_cwnd = t->maxout; 1070 } 1071 } 1072 1073 static struct aoetgt * 1074 gettgt(struct aoedev *d, char *addr) 1075 { 1076 struct aoetgt **t, **e; 1077 1078 t = d->targets; 1079 e = t + d->ntargets; 1080 for (; t < e && *t; t++) 1081 if (memcmp((*t)->addr, addr, sizeof((*t)->addr)) == 0) 1082 return *t; 1083 return NULL; 1084 } 1085 1086 static void 1087 bvcpy(struct sk_buff *skb, struct bio *bio, struct bvec_iter iter, long cnt) 1088 { 1089 int soff = 0; 1090 struct bio_vec bv; 1091 1092 iter.bi_size = cnt; 1093 1094 __bio_for_each_segment(bv, bio, iter, iter) { 1095 char *p = page_address(bv.bv_page) + bv.bv_offset; 1096 skb_copy_bits(skb, soff, p, bv.bv_len); 1097 soff += bv.bv_len; 1098 } 1099 } 1100 1101 void 1102 aoe_end_request(struct aoedev *d, struct request *rq, int fastfail) 1103 { 1104 struct bio *bio; 1105 int bok; 1106 struct request_queue *q; 1107 1108 q = d->blkq; 1109 if (rq == d->ip.rq) 1110 d->ip.rq = NULL; 1111 do { 1112 bio = rq->bio; 1113 bok = !fastfail && !bio->bi_error; 1114 } while (__blk_end_request(rq, bok ? 0 : -EIO, bio->bi_iter.bi_size)); 1115 1116 /* cf. http://lkml.org/lkml/2006/10/31/28 */ 1117 if (!fastfail) 1118 __blk_run_queue(q); 1119 } 1120 1121 static void 1122 aoe_end_buf(struct aoedev *d, struct buf *buf) 1123 { 1124 struct request *rq; 1125 unsigned long n; 1126 1127 if (buf == d->ip.buf) 1128 d->ip.buf = NULL; 1129 rq = buf->rq; 1130 bio_pagedec(buf->bio); 1131 mempool_free(buf, d->bufpool); 1132 n = (unsigned long) rq->special; 1133 rq->special = (void *) --n; 1134 if (n == 0) 1135 aoe_end_request(d, rq, 0); 1136 } 1137 1138 static void 1139 ktiocomplete(struct frame *f) 1140 { 1141 struct aoe_hdr *hin, *hout; 1142 struct aoe_atahdr *ahin, *ahout; 1143 struct buf *buf; 1144 struct sk_buff *skb; 1145 struct aoetgt *t; 1146 struct aoeif *ifp; 1147 struct aoedev *d; 1148 long n; 1149 int untainted; 1150 1151 if (f == NULL) 1152 return; 1153 1154 t = f->t; 1155 d = t->d; 1156 skb = f->r_skb; 1157 buf = f->buf; 1158 if (f->flags & FFL_PROBE) 1159 goto out; 1160 if (!skb) /* just fail the buf. */ 1161 goto noskb; 1162 1163 hout = (struct aoe_hdr *) skb_mac_header(f->skb); 1164 ahout = (struct aoe_atahdr *) (hout+1); 1165 1166 hin = (struct aoe_hdr *) skb->data; 1167 skb_pull(skb, sizeof(*hin)); 1168 ahin = (struct aoe_atahdr *) skb->data; 1169 skb_pull(skb, sizeof(*ahin)); 1170 if (ahin->cmdstat & 0xa9) { /* these bits cleared on success */ 1171 pr_err("aoe: ata error cmd=%2.2Xh stat=%2.2Xh from e%ld.%d\n", 1172 ahout->cmdstat, ahin->cmdstat, 1173 d->aoemajor, d->aoeminor); 1174 noskb: if (buf) 1175 buf->bio->bi_error = -EIO; 1176 goto out; 1177 } 1178 1179 n = ahout->scnt << 9; 1180 switch (ahout->cmdstat) { 1181 case ATA_CMD_PIO_READ: 1182 case ATA_CMD_PIO_READ_EXT: 1183 if (skb->len < n) { 1184 pr_err("%s e%ld.%d. skb->len=%d need=%ld\n", 1185 "aoe: runt data size in read from", 1186 (long) d->aoemajor, d->aoeminor, 1187 skb->len, n); 1188 buf->bio->bi_error = -EIO; 1189 break; 1190 } 1191 if (n > f->iter.bi_size) { 1192 pr_err_ratelimited("%s e%ld.%d. bytes=%ld need=%u\n", 1193 "aoe: too-large data size in read from", 1194 (long) d->aoemajor, d->aoeminor, 1195 n, f->iter.bi_size); 1196 buf->bio->bi_error = -EIO; 1197 break; 1198 } 1199 bvcpy(skb, f->buf->bio, f->iter, n); 1200 case ATA_CMD_PIO_WRITE: 1201 case ATA_CMD_PIO_WRITE_EXT: 1202 spin_lock_irq(&d->lock); 1203 ifp = getif(t, skb->dev); 1204 if (ifp) 1205 ifp->lost = 0; 1206 spin_unlock_irq(&d->lock); 1207 break; 1208 case ATA_CMD_ID_ATA: 1209 if (skb->len < 512) { 1210 pr_info("%s e%ld.%d. skb->len=%d need=512\n", 1211 "aoe: runt data size in ataid from", 1212 (long) d->aoemajor, d->aoeminor, 1213 skb->len); 1214 break; 1215 } 1216 if (skb_linearize(skb)) 1217 break; 1218 spin_lock_irq(&d->lock); 1219 ataid_complete(d, t, skb->data); 1220 spin_unlock_irq(&d->lock); 1221 break; 1222 default: 1223 pr_info("aoe: unrecognized ata command %2.2Xh for %d.%d\n", 1224 ahout->cmdstat, 1225 be16_to_cpu(get_unaligned(&hin->major)), 1226 hin->minor); 1227 } 1228 out: 1229 spin_lock_irq(&d->lock); 1230 if (t->taint > 0 1231 && --t->taint > 0 1232 && t->nout_probes == 0) { 1233 count_targets(d, &untainted); 1234 if (untainted > 0) { 1235 probe(t); 1236 t->nout_probes++; 1237 } 1238 } 1239 1240 aoe_freetframe(f); 1241 1242 if (buf && --buf->nframesout == 0 && buf->iter.bi_size == 0) 1243 aoe_end_buf(d, buf); 1244 1245 spin_unlock_irq(&d->lock); 1246 aoedev_put(d); 1247 dev_kfree_skb(skb); 1248 } 1249 1250 /* Enters with iocq.lock held. 1251 * Returns true iff responses needing processing remain. 1252 */ 1253 static int 1254 ktio(int id) 1255 { 1256 struct frame *f; 1257 struct list_head *pos; 1258 int i; 1259 int actual_id; 1260 1261 for (i = 0; ; ++i) { 1262 if (i == MAXIOC) 1263 return 1; 1264 if (list_empty(&iocq[id].head)) 1265 return 0; 1266 pos = iocq[id].head.next; 1267 list_del(pos); 1268 f = list_entry(pos, struct frame, head); 1269 spin_unlock_irq(&iocq[id].lock); 1270 ktiocomplete(f); 1271 1272 /* Figure out if extra threads are required. */ 1273 actual_id = f->t->d->aoeminor % ncpus; 1274 1275 if (!kts[actual_id].active) { 1276 BUG_ON(id != 0); 1277 mutex_lock(&ktio_spawn_lock); 1278 if (!kts[actual_id].active 1279 && aoe_ktstart(&kts[actual_id]) == 0) 1280 kts[actual_id].active = 1; 1281 mutex_unlock(&ktio_spawn_lock); 1282 } 1283 spin_lock_irq(&iocq[id].lock); 1284 } 1285 } 1286 1287 static int 1288 kthread(void *vp) 1289 { 1290 struct ktstate *k; 1291 DECLARE_WAITQUEUE(wait, current); 1292 int more; 1293 1294 k = vp; 1295 current->flags |= PF_NOFREEZE; 1296 set_user_nice(current, -10); 1297 complete(&k->rendez); /* tell spawner we're running */ 1298 do { 1299 spin_lock_irq(k->lock); 1300 more = k->fn(k->id); 1301 if (!more) { 1302 add_wait_queue(k->waitq, &wait); 1303 __set_current_state(TASK_INTERRUPTIBLE); 1304 } 1305 spin_unlock_irq(k->lock); 1306 if (!more) { 1307 schedule(); 1308 remove_wait_queue(k->waitq, &wait); 1309 } else 1310 cond_resched(); 1311 } while (!kthread_should_stop()); 1312 complete(&k->rendez); /* tell spawner we're stopping */ 1313 return 0; 1314 } 1315 1316 void 1317 aoe_ktstop(struct ktstate *k) 1318 { 1319 kthread_stop(k->task); 1320 wait_for_completion(&k->rendez); 1321 } 1322 1323 int 1324 aoe_ktstart(struct ktstate *k) 1325 { 1326 struct task_struct *task; 1327 1328 init_completion(&k->rendez); 1329 task = kthread_run(kthread, k, "%s", k->name); 1330 if (task == NULL || IS_ERR(task)) 1331 return -ENOMEM; 1332 k->task = task; 1333 wait_for_completion(&k->rendez); /* allow kthread to start */ 1334 init_completion(&k->rendez); /* for waiting for exit later */ 1335 return 0; 1336 } 1337 1338 /* pass it off to kthreads for processing */ 1339 static void 1340 ktcomplete(struct frame *f, struct sk_buff *skb) 1341 { 1342 int id; 1343 ulong flags; 1344 1345 f->r_skb = skb; 1346 id = f->t->d->aoeminor % ncpus; 1347 spin_lock_irqsave(&iocq[id].lock, flags); 1348 if (!kts[id].active) { 1349 spin_unlock_irqrestore(&iocq[id].lock, flags); 1350 /* The thread with id has not been spawned yet, 1351 * so delegate the work to the main thread and 1352 * try spawning a new thread. 1353 */ 1354 id = 0; 1355 spin_lock_irqsave(&iocq[id].lock, flags); 1356 } 1357 list_add_tail(&f->head, &iocq[id].head); 1358 spin_unlock_irqrestore(&iocq[id].lock, flags); 1359 wake_up(&ktiowq[id]); 1360 } 1361 1362 struct sk_buff * 1363 aoecmd_ata_rsp(struct sk_buff *skb) 1364 { 1365 struct aoedev *d; 1366 struct aoe_hdr *h; 1367 struct frame *f; 1368 u32 n; 1369 ulong flags; 1370 char ebuf[128]; 1371 u16 aoemajor; 1372 1373 h = (struct aoe_hdr *) skb->data; 1374 aoemajor = be16_to_cpu(get_unaligned(&h->major)); 1375 d = aoedev_by_aoeaddr(aoemajor, h->minor, 0); 1376 if (d == NULL) { 1377 snprintf(ebuf, sizeof ebuf, "aoecmd_ata_rsp: ata response " 1378 "for unknown device %d.%d\n", 1379 aoemajor, h->minor); 1380 aoechr_error(ebuf); 1381 return skb; 1382 } 1383 1384 spin_lock_irqsave(&d->lock, flags); 1385 1386 n = be32_to_cpu(get_unaligned(&h->tag)); 1387 f = getframe(d, n); 1388 if (f) { 1389 calc_rttavg(d, f->t, tsince_hr(f)); 1390 f->t->nout--; 1391 if (f->flags & FFL_PROBE) 1392 f->t->nout_probes--; 1393 } else { 1394 f = getframe_deferred(d, n); 1395 if (f) { 1396 calc_rttavg(d, NULL, tsince_hr(f)); 1397 } else { 1398 calc_rttavg(d, NULL, tsince(n)); 1399 spin_unlock_irqrestore(&d->lock, flags); 1400 aoedev_put(d); 1401 snprintf(ebuf, sizeof(ebuf), 1402 "%15s e%d.%d tag=%08x@%08lx s=%pm d=%pm\n", 1403 "unexpected rsp", 1404 get_unaligned_be16(&h->major), 1405 h->minor, 1406 get_unaligned_be32(&h->tag), 1407 jiffies, 1408 h->src, 1409 h->dst); 1410 aoechr_error(ebuf); 1411 return skb; 1412 } 1413 } 1414 aoecmd_work(d); 1415 1416 spin_unlock_irqrestore(&d->lock, flags); 1417 1418 ktcomplete(f, skb); 1419 1420 /* 1421 * Note here that we do not perform an aoedev_put, as we are 1422 * leaving this reference for the ktio to release. 1423 */ 1424 return NULL; 1425 } 1426 1427 void 1428 aoecmd_cfg(ushort aoemajor, unsigned char aoeminor) 1429 { 1430 struct sk_buff_head queue; 1431 1432 __skb_queue_head_init(&queue); 1433 aoecmd_cfg_pkts(aoemajor, aoeminor, &queue); 1434 aoenet_xmit(&queue); 1435 } 1436 1437 struct sk_buff * 1438 aoecmd_ata_id(struct aoedev *d) 1439 { 1440 struct aoe_hdr *h; 1441 struct aoe_atahdr *ah; 1442 struct frame *f; 1443 struct sk_buff *skb; 1444 struct aoetgt *t; 1445 1446 f = newframe(d); 1447 if (f == NULL) 1448 return NULL; 1449 1450 t = *d->tgt; 1451 1452 /* initialize the headers & frame */ 1453 skb = f->skb; 1454 h = (struct aoe_hdr *) skb_mac_header(skb); 1455 ah = (struct aoe_atahdr *) (h+1); 1456 skb_put(skb, sizeof *h + sizeof *ah); 1457 memset(h, 0, skb->len); 1458 f->tag = aoehdr_atainit(d, t, h); 1459 fhash(f); 1460 t->nout++; 1461 f->waited = 0; 1462 f->waited_total = 0; 1463 1464 /* set up ata header */ 1465 ah->scnt = 1; 1466 ah->cmdstat = ATA_CMD_ID_ATA; 1467 ah->lba3 = 0xa0; 1468 1469 skb->dev = t->ifp->nd; 1470 1471 d->rttavg = RTTAVG_INIT; 1472 d->rttdev = RTTDEV_INIT; 1473 d->timer.function = rexmit_timer; 1474 1475 skb = skb_clone(skb, GFP_ATOMIC); 1476 if (skb) { 1477 do_gettimeofday(&f->sent); 1478 f->sent_jiffs = (u32) jiffies; 1479 } 1480 1481 return skb; 1482 } 1483 1484 static struct aoetgt ** 1485 grow_targets(struct aoedev *d) 1486 { 1487 ulong oldn, newn; 1488 struct aoetgt **tt; 1489 1490 oldn = d->ntargets; 1491 newn = oldn * 2; 1492 tt = kcalloc(newn, sizeof(*d->targets), GFP_ATOMIC); 1493 if (!tt) 1494 return NULL; 1495 memmove(tt, d->targets, sizeof(*d->targets) * oldn); 1496 d->tgt = tt + (d->tgt - d->targets); 1497 kfree(d->targets); 1498 d->targets = tt; 1499 d->ntargets = newn; 1500 1501 return &d->targets[oldn]; 1502 } 1503 1504 static struct aoetgt * 1505 addtgt(struct aoedev *d, char *addr, ulong nframes) 1506 { 1507 struct aoetgt *t, **tt, **te; 1508 1509 tt = d->targets; 1510 te = tt + d->ntargets; 1511 for (; tt < te && *tt; tt++) 1512 ; 1513 1514 if (tt == te) { 1515 tt = grow_targets(d); 1516 if (!tt) 1517 goto nomem; 1518 } 1519 t = kzalloc(sizeof(*t), GFP_ATOMIC); 1520 if (!t) 1521 goto nomem; 1522 t->nframes = nframes; 1523 t->d = d; 1524 memcpy(t->addr, addr, sizeof t->addr); 1525 t->ifp = t->ifs; 1526 aoecmd_wreset(t); 1527 t->maxout = t->nframes / 2; 1528 INIT_LIST_HEAD(&t->ffree); 1529 return *tt = t; 1530 1531 nomem: 1532 pr_info("aoe: cannot allocate memory to add target\n"); 1533 return NULL; 1534 } 1535 1536 static void 1537 setdbcnt(struct aoedev *d) 1538 { 1539 struct aoetgt **t, **e; 1540 int bcnt = 0; 1541 1542 t = d->targets; 1543 e = t + d->ntargets; 1544 for (; t < e && *t; t++) 1545 if (bcnt == 0 || bcnt > (*t)->minbcnt) 1546 bcnt = (*t)->minbcnt; 1547 if (bcnt != d->maxbcnt) { 1548 d->maxbcnt = bcnt; 1549 pr_info("aoe: e%ld.%d: setting %d byte data frames\n", 1550 d->aoemajor, d->aoeminor, bcnt); 1551 } 1552 } 1553 1554 static void 1555 setifbcnt(struct aoetgt *t, struct net_device *nd, int bcnt) 1556 { 1557 struct aoedev *d; 1558 struct aoeif *p, *e; 1559 int minbcnt; 1560 1561 d = t->d; 1562 minbcnt = bcnt; 1563 p = t->ifs; 1564 e = p + NAOEIFS; 1565 for (; p < e; p++) { 1566 if (p->nd == NULL) 1567 break; /* end of the valid interfaces */ 1568 if (p->nd == nd) { 1569 p->bcnt = bcnt; /* we're updating */ 1570 nd = NULL; 1571 } else if (minbcnt > p->bcnt) 1572 minbcnt = p->bcnt; /* find the min interface */ 1573 } 1574 if (nd) { 1575 if (p == e) { 1576 pr_err("aoe: device setifbcnt failure; too many interfaces.\n"); 1577 return; 1578 } 1579 dev_hold(nd); 1580 p->nd = nd; 1581 p->bcnt = bcnt; 1582 } 1583 t->minbcnt = minbcnt; 1584 setdbcnt(d); 1585 } 1586 1587 void 1588 aoecmd_cfg_rsp(struct sk_buff *skb) 1589 { 1590 struct aoedev *d; 1591 struct aoe_hdr *h; 1592 struct aoe_cfghdr *ch; 1593 struct aoetgt *t; 1594 ulong flags, aoemajor; 1595 struct sk_buff *sl; 1596 struct sk_buff_head queue; 1597 u16 n; 1598 1599 sl = NULL; 1600 h = (struct aoe_hdr *) skb_mac_header(skb); 1601 ch = (struct aoe_cfghdr *) (h+1); 1602 1603 /* 1604 * Enough people have their dip switches set backwards to 1605 * warrant a loud message for this special case. 1606 */ 1607 aoemajor = get_unaligned_be16(&h->major); 1608 if (aoemajor == 0xfff) { 1609 printk(KERN_ERR "aoe: Warning: shelf address is all ones. " 1610 "Check shelf dip switches.\n"); 1611 return; 1612 } 1613 if (aoemajor == 0xffff) { 1614 pr_info("aoe: e%ld.%d: broadcast shelf number invalid\n", 1615 aoemajor, (int) h->minor); 1616 return; 1617 } 1618 if (h->minor == 0xff) { 1619 pr_info("aoe: e%ld.%d: broadcast slot number invalid\n", 1620 aoemajor, (int) h->minor); 1621 return; 1622 } 1623 1624 n = be16_to_cpu(ch->bufcnt); 1625 if (n > aoe_maxout) /* keep it reasonable */ 1626 n = aoe_maxout; 1627 1628 d = aoedev_by_aoeaddr(aoemajor, h->minor, 1); 1629 if (d == NULL) { 1630 pr_info("aoe: device allocation failure\n"); 1631 return; 1632 } 1633 1634 spin_lock_irqsave(&d->lock, flags); 1635 1636 t = gettgt(d, h->src); 1637 if (t) { 1638 t->nframes = n; 1639 if (n < t->maxout) 1640 aoecmd_wreset(t); 1641 } else { 1642 t = addtgt(d, h->src, n); 1643 if (!t) 1644 goto bail; 1645 } 1646 n = skb->dev->mtu; 1647 n -= sizeof(struct aoe_hdr) + sizeof(struct aoe_atahdr); 1648 n /= 512; 1649 if (n > ch->scnt) 1650 n = ch->scnt; 1651 n = n ? n * 512 : DEFAULTBCNT; 1652 setifbcnt(t, skb->dev, n); 1653 1654 /* don't change users' perspective */ 1655 if (d->nopen == 0) { 1656 d->fw_ver = be16_to_cpu(ch->fwver); 1657 sl = aoecmd_ata_id(d); 1658 } 1659 bail: 1660 spin_unlock_irqrestore(&d->lock, flags); 1661 aoedev_put(d); 1662 if (sl) { 1663 __skb_queue_head_init(&queue); 1664 __skb_queue_tail(&queue, sl); 1665 aoenet_xmit(&queue); 1666 } 1667 } 1668 1669 void 1670 aoecmd_wreset(struct aoetgt *t) 1671 { 1672 t->maxout = 1; 1673 t->ssthresh = t->nframes / 2; 1674 t->next_cwnd = t->nframes; 1675 } 1676 1677 void 1678 aoecmd_cleanslate(struct aoedev *d) 1679 { 1680 struct aoetgt **t, **te; 1681 1682 d->rttavg = RTTAVG_INIT; 1683 d->rttdev = RTTDEV_INIT; 1684 d->maxbcnt = 0; 1685 1686 t = d->targets; 1687 te = t + d->ntargets; 1688 for (; t < te && *t; t++) 1689 aoecmd_wreset(*t); 1690 } 1691 1692 void 1693 aoe_failbuf(struct aoedev *d, struct buf *buf) 1694 { 1695 if (buf == NULL) 1696 return; 1697 buf->iter.bi_size = 0; 1698 buf->bio->bi_error = -EIO; 1699 if (buf->nframesout == 0) 1700 aoe_end_buf(d, buf); 1701 } 1702 1703 void 1704 aoe_flush_iocq(void) 1705 { 1706 int i; 1707 1708 for (i = 0; i < ncpus; i++) { 1709 if (kts[i].active) 1710 aoe_flush_iocq_by_index(i); 1711 } 1712 } 1713 1714 void 1715 aoe_flush_iocq_by_index(int id) 1716 { 1717 struct frame *f; 1718 struct aoedev *d; 1719 LIST_HEAD(flist); 1720 struct list_head *pos; 1721 struct sk_buff *skb; 1722 ulong flags; 1723 1724 spin_lock_irqsave(&iocq[id].lock, flags); 1725 list_splice_init(&iocq[id].head, &flist); 1726 spin_unlock_irqrestore(&iocq[id].lock, flags); 1727 while (!list_empty(&flist)) { 1728 pos = flist.next; 1729 list_del(pos); 1730 f = list_entry(pos, struct frame, head); 1731 d = f->t->d; 1732 skb = f->r_skb; 1733 spin_lock_irqsave(&d->lock, flags); 1734 if (f->buf) { 1735 f->buf->nframesout--; 1736 aoe_failbuf(d, f->buf); 1737 } 1738 aoe_freetframe(f); 1739 spin_unlock_irqrestore(&d->lock, flags); 1740 dev_kfree_skb(skb); 1741 aoedev_put(d); 1742 } 1743 } 1744 1745 int __init 1746 aoecmd_init(void) 1747 { 1748 void *p; 1749 int i; 1750 int ret; 1751 1752 /* get_zeroed_page returns page with ref count 1 */ 1753 p = (void *) get_zeroed_page(GFP_KERNEL | __GFP_REPEAT); 1754 if (!p) 1755 return -ENOMEM; 1756 empty_page = virt_to_page(p); 1757 1758 ncpus = num_online_cpus(); 1759 1760 iocq = kcalloc(ncpus, sizeof(struct iocq_ktio), GFP_KERNEL); 1761 if (!iocq) 1762 return -ENOMEM; 1763 1764 kts = kcalloc(ncpus, sizeof(struct ktstate), GFP_KERNEL); 1765 if (!kts) { 1766 ret = -ENOMEM; 1767 goto kts_fail; 1768 } 1769 1770 ktiowq = kcalloc(ncpus, sizeof(wait_queue_head_t), GFP_KERNEL); 1771 if (!ktiowq) { 1772 ret = -ENOMEM; 1773 goto ktiowq_fail; 1774 } 1775 1776 mutex_init(&ktio_spawn_lock); 1777 1778 for (i = 0; i < ncpus; i++) { 1779 INIT_LIST_HEAD(&iocq[i].head); 1780 spin_lock_init(&iocq[i].lock); 1781 init_waitqueue_head(&ktiowq[i]); 1782 snprintf(kts[i].name, sizeof(kts[i].name), "aoe_ktio%d", i); 1783 kts[i].fn = ktio; 1784 kts[i].waitq = &ktiowq[i]; 1785 kts[i].lock = &iocq[i].lock; 1786 kts[i].id = i; 1787 kts[i].active = 0; 1788 } 1789 kts[0].active = 1; 1790 if (aoe_ktstart(&kts[0])) { 1791 ret = -ENOMEM; 1792 goto ktstart_fail; 1793 } 1794 return 0; 1795 1796 ktstart_fail: 1797 kfree(ktiowq); 1798 ktiowq_fail: 1799 kfree(kts); 1800 kts_fail: 1801 kfree(iocq); 1802 1803 return ret; 1804 } 1805 1806 void 1807 aoecmd_exit(void) 1808 { 1809 int i; 1810 1811 for (i = 0; i < ncpus; i++) 1812 if (kts[i].active) 1813 aoe_ktstop(&kts[i]); 1814 1815 aoe_flush_iocq(); 1816 1817 /* Free up the iocq and thread speicific configuration 1818 * allocated during startup. 1819 */ 1820 kfree(iocq); 1821 kfree(kts); 1822 kfree(ktiowq); 1823 1824 free_page((unsigned long) page_address(empty_page)); 1825 empty_page = NULL; 1826 } 1827